a combination of static or varying electric and magnetic fields, used to focus streams of electrons in a manner similar to that of an optical lens.
a system, such as an arrangement of electrodes or magnets, that produces a field for focusing a beam of electrons
- Electron micrograph
noun 1. a photograph or image of a specimen taken using an electron microscope
noun 1. a microscope of extremely high power that uses beams of electrons focused by magnetic lenses instead of rays of light, the magnified image being formed on a fluorescent screen or recorded on a photographic plate: its magnification is substantially greater than that of any optical microscope. noun 1. a powerful type of microscope […]
- Electron model
electronics A model of semiconductor behaviour in which donors contribute the charge of an electron, and acceptors contribute a space for same, in effect contributing a fictional positive charge of similiar magnitude. Physicists use the electron model. Some language theorists consider language and the electron to be models in themselves. Contrast hole model. (1995-10-06)
noun, Electronics. 1. a vacuum tube containing a number of dynodes that serve to amplify the flow of electrons from the cathode by means of secondary emission. noun 1. (physics) a device for amplifying and measuring a flux of electrons. Each electron hits an anode surface and releases secondary electrons that are accelerated to a […]